Update peaceiris/actions-mdbook action to v2 (#617)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[peaceiris/actions-mdbook](https://togithub.com/peaceiris/actions-mdbook)
| action | major | `v1` -> `v2` |

---

### Release Notes

<details>
<summary>peaceiris/actions-mdbook (peaceiris/actions-mdbook)</summary>

###
[`v2`](https://togithub.com/peaceiris/actions-mdbook/compare/v1...v2)

[Compare
Source](https://togithub.com/peaceiris/actions-mdbook/compare/v1...v2)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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.github/workflows/build-and-test.yml

@@ -40,7 +40,7 @@ jobs:
         run: cargo install --path emulator/test-runner --verbose
       - uses: extractions/setup-just@v2
       - name: Setup mdBook
-        uses: peaceiris/actions-mdbook@v1
+        uses: peaceiris/actions-mdbook@v2
         with:
           mdbook-version: "0.4.13"
       - name: Build and test all crates

.github/workflows/build-site.yml

@@ -30,7 +30,7 @@ jobs:
           key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}--npm--${{ hashFiles('**/package-lock.json') }}
       - uses: extractions/setup-just@v2
       - name: Setup mdBook
-        uses: peaceiris/actions-mdbook@v1
+        uses: peaceiris/actions-mdbook@v2
         with:
           mdbook-version: "0.4.13"
       - name: Build website